Rendering is optimized for static geometry. The primitive's vertices are not going to be updated with Set() or SetPartial() calls. Calls to SetPartial() will fail. Calls to Set() are allowed but may not be as efficient as SetHintFrequent.

Partial

Rendering is optimized for dynamic geometry. The primitive's vertices are expected to be updated with SetPartial() - some or all of the vertices will change but the number of vertices will not.

Frequent

Rendering is optimized for streaming geometry. The primitive's vertices are expected to be updated with Set() - all the vertices will change and/or the number of vertices will change. Calls to SetPartial() will fail.